1. Field of the Invention
This invention relates to a centrifuge rotor and, in particular, to a suspension system for a centrifuge rotor.
2. Description of the Prior Art
An important consideration when using a centrifuge apparatus is insuring that the load carried by the rotor is in balance with respect thereto. This concern is well-founded since, as rotational speed increases through the critical value, rotor unbalance manifests itself as vibration. Depending upon the magnitude of the unbalance, such vibration may be sufficient to damage the centrifuge apparatus.
For a rotating body, such as a centrifuge rotor, to pass through its critical speed, two events must occur simultaneously. First, the rotor's principle axis, the axis through the rotor's center of gravity, must lie parallel to the rotor's spin axis, the axis passing through the geometric center of the rotor. Second, the rotor's center of gravity must lie on the spin axis. If these two events were enabled to occur more quickly after rotor start-up, then the rotor would pass through its critical speed at an earlier time (i.e., at a lower speed) thus reducing the vibration caused by a given amount of rotor unbalance.
In view of the foregoing it would be advantageous to provide a centrifuge that would maintain vibratory forces at a minimum, thus increasing the amount of unbalance that the centrifuge would be able to tolerate. One manner of accomplishing this end is to reduce the critical speed of the rotor. By lowering the rotor's critical speed, the vibration imposed on the centrifuge by a given rotor unbalance is commensurately reduced.